java - Hibernate 合并父级并更新惰性子级集合列表

Question

当我执行合并父表时遇到问题，现有的子记录将被插入而不是更新。

例如，Member(Parent) 和 Address(Child) 表，

    public class Member implements Serializable{
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name="id")
    private int id;

    @OneToMany(fetch = FetchType.LAZY, mappedBy = "member", cascade = CascadeType.ALL)
        public List<Address> addressList;
}


public class Address implements Serializable {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "id")
    private int address_id;

    @Column(name = "member_id")
    private int mem_id;
    @ManyToOne(fetch = FetchType.EAGER)
    @JoinColumns({
        @JoinColumn(name = "member_id", referencedColumnName = "id", insertable = false, updatable = false)
    })
    public Member member;
}

当我执行更改和合并(成员)时，将插入地址记录而不是更新现有记录。

有谁知道这是什么原因吗？

Answer 1

当您执行更改时，您是否设置了正确的address_id？ 。进行一些调试，发现address_id与地址表中现有的id匹配。

在我的方法类中将如下所示。我认为不需要 member_id 属性。因为它与成员的 id 属性相同。

公共(public)类地址实现可序列化{

@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(name = "id")
private int address_id;


@ManyToOne(fetch = FetchType.EAGER)
@JoinColumn(name = "member_id",  nullable = false)
public Member member;

public void setMember(Member member) {
    this.member = member;
}

}